Rigenolides B and C, conjugates of norsecoiridoid and secoiridoid glucoside from Gentiana rigescens Franch.

Abstract Two new conjugates of norsecoiridoid and secoiridoid glucoside, rigenolides B ( 1 ) and C ( 2 ), were isolated from a Chinese herbal medicine Gentiana rigescens Franch. Their structures were established by comprehensive spectroscopic analysis. The absolute configurations of 1 and 2 were elucidated by comparison of the ECD spectra with TDDFT calculated spectra.